Telephone-exchange system



H. P. CLAUSEN.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION HLED JULY 19,1919.

1 97,034, Patented Nov" 15, 1921.

2 $HEETSSHEET I.

/n ve/vfo Wang/6 0M146 6 7 by Aff'y.

H. P. CLAUSEN. v TELEPHONE EXCHANGE SYSTEM. APPLlCATiON FILED JULY 19,1919. 1 397,034, Patented Nov. 15, 1921.

2 SHEETS-SHEET 2- by Why- STATES.

PATENT osrics.

HENRY P. GLAUSEN, OF MOUNT VERNON, NEW YORK, ASSIGNOR TO WESTERN ELEG- TEIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A COBPQBATIQN OF NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

raamosa.

Application filed July 19,

To all whom it may concern:

Be it known that I, HENRY P. OLAUSEN, a citizen of the United States, residing at Mount Vernon, in the county of VVestchester, State of New York, have invented certain new and useful Improvements in Telephone-Exchange Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to improvements in telephone exchange systems and has particular reference to special service systems for machine switching telephone exchanges.

Means have previously been devised, in machine switching systems, for summoning a particular person, when such person is away from his instrument. This means, under the control of the calling subscriber, will, when operated, actuate special signals distributed throughout various sections of a building or establishment. The wanted subscriber, upon hearing a special signal, can connect to the calling line by operating the dial at any one of a number of substations which are also conveniently dis tributed throughout the building.

An object of this invention is to provide means whereby a particular person, who is away from his instrument when a call comes in, may be summoned by the automatic operation of a special signal without any special act of the calling party.

Another object is the provision of means for operating said special signal at the expiration of a predetermined period of time following the application of the usual ringing current to the substation apparatus of the called subscriber.

The inventive idea involved is capable of receiving a variety of expressions one of which, for the purpose of illustrating the invention, is shown in the accompanying drawings; but it is to be expressly understood that said drawings are employed merely for the purpose of facilitating the description of the invention as a whole and not to define the limits thereof, reference being had to the appended claims for this purpose.

Figures 1 and 2, with Fig. 2 above Fig. 1, illustrate diagrammatically the circuit arrangement employed in carrying out the invention.

The invention is particularly adapted for Specification of Letters Patent.

Patented Nov. 15, 1921.

1919. Scria1No.312,007.

and is shown in the drawing as applied to a private branch exchange although it will be understood that the same may be used equally as well in larger exchanges without de arting from the spirit of the invention.

riefly, a special signal circuit is installed in the building in which the exchange is located so that signals transmitted may be heard in the various parts of the establishment. The special signaling is preferably in code form with one code representing each particular person who may be provided with this special service feature. Associated with each connector or final selector switch is a mechanism which becomes effective after the lapse of a predetermined period following the application of the ordinary ringing current to the substation apparatus of a wanted line. Said mechanism causes the operation of the special signaling circuit to ring the code of the particular party wanted until said party answers or the call is abandoned.

It is thought that the invention will now be fully understood from the following detailed description of the operation. Upon the initiation of a call by the removal of the 7 receiver from the switchhook at substation A, a line or finder switch (not shown) of any construction well known in the art is operated to extend the line to the connector switch B. A circuit for the line relay 1 is then closed, which circuit extends from grounded battery, through right winding of said'relay, inner alternate contacts of relay 2, the calling subscribers substation apparatus, outer alternate contact of relay 2 and left winding of relay 1 to ground. Relay 1, in energizing, establishes a circuit for first slow-to-release relay 3 which, by attracting its outer armature, applies busy (ground) potential to conductor 4 which will prevent the switch from being seized by any other line or finder switch. The calling subscriber at substation A may now manipulate his sending device to transmit sets of impulses in accordance with the digits of the wanted substation C. The first retraction of the armature of relay 1 in response to the first impulse establishes a circuit extending from grounded battery, side-switch wiper 5 in position 1, winding of primary magnet 6, winding of the second slow-to-remanner.

ture of relay 3, back contact and armature of relay 1 to ground. Magnet 6 operates in response to the first set of impulses to drive the brushes 8, 9, 10 and 11 of switch B to the row of contacts in the terminal back of said switch in which the contacts individual to the called line are located. Relay 7 op erates in series with magnet-6 and together with relay 3 maintains its armature attracted during the transmission of impulses. When relay 7 is first energized the ground is ex- .tended from the, armature thereof through its alternate contact and winding of escape magnet 12 to grounded battery. This magnet energizes but in so doing does not affect the side-switch wipers- At the termination of the first set of impulses, relay 7, after an interval, releases and causes deenergization of escape magnet 12 which thereupon moves the side-switch wipers into position 2. In response to the second set of impulses corresponding to theunits digit of the wanted line, a circuit is 110w established extending from grounded battery, through side-switch wiper 5 in position 2, winding of the secondary stepping magnet 13, left armature and back contact of test relay 14, winding of relay 7, front contact and inner armature of relay 3 and back contact armature of relay '1 to ground. Magnet 13 operates to step the brushes of the switch onto the terminals individual to the called line.

If the called line is busy, which condition is denoted by ground upon the test terminal 15, a circuit is established from grounded battery, winding of escape magnet 12, alternate contact of relay 7 asthe same releases its armature at the termination of the set of impulses, winding and alternate contact of relay 14, side-switch wiper 16 in position 2, brush 10 and terminal 15 to ground. This circuit will maintain escape-magnet 12 energized and also operate relay 14 which locks up through its alternate contact and inner right armature to ground through the off-normal contact 17 which was closed upon "the first step of the switch. By attracting its outer right armature, relay 14 connects the busy tone apparatus BZ to the calling line 111 a manner well known in the art and the calling subscriber, upon hearing this switchhoolr. i This will cause the release or". theline or finder switch in a well known Relays 1 and 3 also retract their armatures and in so doing establish a circuit for release magnet 18 extending from grounded battery, winding of said magnet, off-normal contact 19 which was closed upon the first step of the switch, backcontact and inner armature of relay 3 and baclr'contact and armature of relay 1 to ground. j Release magnet 18 operates to return the brushes of the switch and side-switch mechanism to their normal positions, whereupon off-nor- .mal contacts 17 and 19 arealso restored to normal and the switch is again in position for another operation.

Assuming now thatrthe called substation C is idle and that the wanted subscriber is within hearing distance of his own telephone bell, when the brushes of switch 15 engage terminals individual to the wanted line escape magnet 12 will fail to find ground upon test terminal 15 with the result that said magnet releases and moves the side-switch wipers into position 3. A circuit is then closed for relay 20 from battery, through its winding and sideswitch wiper 16 in position 3 to ground. A circuit is also established extending from grounded battery, side-switch wiper 21 in position 3, right-hand armature and contact of relay 27, through the winding of ringing relay 22, contact 23 in its normal position and a conducting se ment of interrupter 24 to ground. interrupter 24 will cause the intermittent operation of relay 22 and each time said relay attracts its armatures, ringing current is applied to the called line extending from a source of ringing current, front contact and inner upper armature of relay 22, lower armature and front contact of relay 20, brush 9, terminal 25, substation apparatus G including the ringer thereat, terminal 26, brush 8, front contact and upper armature of relay 20, outer upper armature and front contact of relay 22 to ground. hen the called subscriber responds by removing his receiver from its hook, a circuit is closed for the supervisory relay 2 which, in attracting its left armatures, maintains the circuit for relay 1 through said armatures and the alternate contacts thereof. By attracting its right armature, a circuit is established for relay 27, extending from grounded battery, sideswitch wiper 21 in position 3, winding of relay 27, front contact and right armature of relay 2, off-normal contact 17 to ground.

Belay 27 energizes and locks up through its lef armature and front contact to the last mentioned ground. By attracting its right armature, the energizing circuit for relay 22 is permanently opened and the calling line is extended to the called line, whereupon conversation between the parties may proceed. At the termination of the conversation, release of switch B is accomplished in the same manner as previously described by the replacing of the receiver upon its switchhook at the calling substa tion. Y

if, on the other hand, the subscriber who should be at substation C is lsewhere, as for instance in some other part of the building, the ringing current applied to the line will be controlle. for a predetermined length of time by the interrupter 24, at the termination of which time said ringing current is controlled by a continuously rotatable cam 28 individual to the called substation 0. Cam 28 is constructed to produce a special core ringing which will be applied to a plurality of ringer apparatus 29 distributed in convenient places throughout the building. This is done in the following manner: As soon as relay 22 starts to operate to apply the ordinary ringing current to the called line, a circuit is established for dash-pot relay 30 individual to switch B, which circuit extends from grounded battery, winding of said relay, alternate contact and lower armature of relay 22 each time said relay attracts its armatures, back contact and left armature of slow-to-release relay 31 also individual to switch B, and the back contacts and left armatures of all other relays similar to relay 31 and individual to other connector switches, to ground. Each momentary establishment of this circuit in response to each energization of relay 22 is sufficient to move the solenoid of relay 30 upwardly a slight distance so that the upper end of said solenoid will approach contact \Vhen the circuit for relay 30 is opened, the solenoid thereof will not return to normal due to the dash-pot arrangement but will only be retarded a slight distance so that for a predetermined length of time said solenoid will, by degrees, continue to approach said contact 28 and then engages the same with its alternate contact. A circuit is then established extending from grounded battery, side-switch wiper 21 in position 3, back contact and right armature of relay 27, winding of relay 22, contact 23, winding of relay 31, brush 11, terminal 32 and contact spring 33, each time the same is actuated by one of the teeth of cam 28, to ground. Relay 31 energizes in this circuit and, being slow-to-release, will not retract its armatures while the contact spring 33 is in normal position. The attraction of the left armature of relay 81 establishes a holding circuit for relay 30 extending through front contact and left armature of relay 31 and the back contacts and armatures of other relays similar to relay 81 to ground. By reason of the energization of relay 31, it will be apparent that the dashpot relays of other mechanisms shown inclosed in dotted lines and individual to other switches, will be prevented from becoming energized until the rin 'ing of the by removing the receiver from the switchhook at the nearest special substation, such as the one shown at D in Fig. 2. Upon the removal of the receiver from the switchhook at substation D, a circuit is closed for line relay 3% which, in attracting its armature, establishes a circuit for magnet 35 ex tending from grounded battery, right winding of said magnet and armature and contact of relay Eel to ground. Magnet 35 operates its left armatures and opens the circuit of relay 3a and also operates plunger 36 individual to the line of substation D to close the associated spring contacts. This immediately esablishes a circuit for line relay 3? extending from grounded battery, left winding of said relay. back contact and innermost -ower armature of relay 38, contact 39, substation apparatus D, contact 40, inner upper armature and back contact of relay 38 and right winding of relay 3? to ground. Relay 37 energizes and also establishes a circuit for alow-to-release relay 1-1. By attract ing its outer armature, relay i1 establishes a holding circuit for magnet 35 which extends from ground at said armature through contact 42 and left winding of magnet 35 to grounded battery. The wanted subscriber at substation D now manipulates the send ing device there-at to transmit a predetermined number of impulses in response to which the armature of line relay 3'? is vibrated. Each deenergization of relay 3? establishes a circuit which extends from ground, through the armature and back contact of said relay, back contact and outermost lower armature of relay 38, inner armature and front contact of relay 4:1. winding of slow-to-release relay 13 and winding of primary stepping magnet 44k to grounded battery. Magnet a l operates in response to each impulse to step the brushes 15, 46, 4;?

and Q8 of switch E to the row of terminals containing those individual to substation 9. Relay 43 alsoenergizes in the circuit ust described and by attracting its armature establishes an energizing circuit for relay 19 which remains energized over a circuit ex tending from grounded battery, winding of relay 4-9, middle lower armature and back contact of relay 38, front contact and armature of relay 19, back contact and right armature of stepping magnet 50, off-normal contact 51 which was closed upon the first step of the brushes of switch E outer arma armature of magnet 50, oituormal contact 51 and outer armature and front contact of relay 41 to ground. Magnet 50 operates to step the brushes of switch E over the terminals off the selected row and each time that magnet 50 attracts its right armature the locking circuit of relay 4&9 is opened but this relay does not deenergize due to the extension of the locking circuit through brush 17, terminal 52 and side-switch wiper 53 of any other switch similar to switch B to ground. Magnet 50 will therefore continue to operate until the brushes of switch E are stepped onto the set of terminals which will connect the line extending from substation D to the line extending from substation A. When this set of terminals is reached, a circuit is closed for cut-off reay 38 extending from grounded battery, winding of said relay, front contact and outer armature of relay 49, brush 18, terminal 5a, and spring contact 23 to ground. lie 38 energizes to extend the call from substation D and locks up through its uppermost armature and front contact. brush 4E7, terminal 52, side-switch wipers 53 and 16 to ground. By attracting its middle lower armature, the stepping circuit for magnet 50 and locking circuit for relay 19 is permanently opened and said magnet and relay de'e'nergize. By extending the calling line from substation D the energizing circuit for line relay 37 is opened and this relay deenergizes which in turn causes the release of relay 4:1. Magnet 35, however, remains energized over a circuit extending from grounded battery, left winding of said magnet, contact 1-2, oftnormal contact 51, right arma ture and back contact of magnet 50, brush 47, terminal 52 and side-switch wiper and 16 in position 3 to ground. As soon as the brushes 45 and 4:6 engage their respective terminals 55 and 56 and relay 38 energizes, a circuit is established for relay 2 from grounded battery, left-hand winding of said relay over the lower side of the line, terminal 56, brush 16, front contact and innermost lower armature of relay 38, contact 39, substation apparatus D, contact 40, inner upper armature and front contact of relay 38, brush 45, terminal 55, upper side of the line and right winding of relay 2 to ground. Energization of relay 2 causes the operation 01 relay 27 as previously described, with the result that the circuit for ringing relay 22 is permanently opened and the operation of the ringer apparatus 29 and that at substation C stopped. The open ing of the circuit for relay 22 also causes the release of relay 31 which, in retracting its left armature, opens the holding circuit for relay 30 and the solenoid thereof is then returned to normal. Release of relay 31 will now permit the operation of another one of the mechanisms individual to other connecatabse tor switches. Conversation ma now pro ceed between the parties at substations A and D, talking current being supplied to the line of the latter station by relay 2. At the termination of the conversation, the replacor" the receiver upon the switchhook at substation A causes release 01 switch B in the manner previously described. Relay 38 releases as soon as the side-switch wiper 16 of switch B moves from position 3 under the control of release magnet 18 as previously described. Relay 38, in restoring, closes a circuit for release magnet 57, extending from grounded battery, winding of said magnet, oil-normal contact 51, back contact and inner armature of relay ll, outermost lower armature and back contact of relay 33, back contact and armature of relay'37 to ground. hlovement of side-switch wiper 16 from position 3 opens the previously described circuit t'or magnet 35 which then re l ases to restore plunger 36 to normal. He lease magnet 57 operates to restore switch E to its normal position whereupon the switch will be ready for another operation.

What is claimed is:

1. In telephone system, telephone lines, audible signaling devices individual thereto, audible signaling devices common to said lines, and means including automatic switches for selecting a line and automatically actuating its individual signal, means for automatically actuating said common signaling devices at the termination of a. definite period after the operation of the individual signaling device of the selected line, and means whereby a third one of said lines may be connected to the calling line.

2. In telephone system, telephone lines, call bells individual thereto, means including automatic switches for selecting a line and automatically ringing its bell, bells common to said lines, and means automatically rendered effective after a definite lapse of time following the actuating of said individual bell for causing said common bells to give a code signal individual to the called lines, and means whereby a third one of said lines may be connected to the calling line.

3. In a telephone system, telephone lines, call bells individual thereto a generator, mean including automatic switches for selecting a line and automatically applying current from said generator to its bell, bells common to said lines, and means automatically actuated at the termination of a defi- 'nite period after the operation of the individual bell of the calling line for connecting said generator to said common bells to give a code signal, and automatic means whereby a third one of said lines may be conneeted to the calling line.

4. In a telephone system, telephone lines each including a calling signal, a secondary calling signal common to said lines, means individual to each of said lines for operat ing sait secondary calling signal in a different character ic manner, means for selecting one of said lines and operating the signal thercat, and means for actuating said secondary :alling signal after a predetermined lapse of time following the actuation of the first named signal.

in a telephone system, a calling subscribers line, other telephone lines, a signal individual to each of said other lines, a signal common to said other lines, means individual to each of said other lines for causing said common signal to operate in a characteristic manner, and separate means for actuating said common and said individual signals, the actuation of said common signal being independent of the calling subscriber.

6. In a telephone system, a calling subscribers line, other telephone lines, a signal individual to each of said other lines, a signal common to said other lines, means individual to each of said other lines for causing said common signal to operate in a distinctive manner, means for operating said individual signal, and means independent of the calling subscriber for subsequently operating said common signal.

7. In a telephone system, a calling sub scribers line, other telephone lines, a sig-V nal individual to each of said other lines, a signal common to said other lines, means individual to each of said other lines for causing said common signal to operate in a distinctive manner, means for operating said individual signal, and means independent of the calling subscriber for operating said common signal at the termination of a definite period of time after the operation of said individual signal.

8. In a telephone system, telephone lines, a signal individual to each of said lines, a signal common to said lines, separate means for actuating said common and individual signals, machine switching means for interconnecting said lines, means whereby a first one of said lines may call a second one of said lines and actuate said individual signal of said second line, means actuated after a definite lapse of time following the operation of said individual signal. for actuating said common signal, and means whereby a third one of said lines may establish a conversational circuit to said first line.

9. In a telephone system, telephone lines, an individual signal for each of said lines, a common signal for said lines, means associated with each of said lines for operating said common signal in a distinctive manner, machine switching means for establishing the connection between the first one of said lines and a second one of said lines, means included in said machine switching means for causing said individual signal of said an individual signal for each of said lines,

a common signal for said lines, means associated with each of said lines-for operating said common signal-in a distinctive manner, machine switching means for establishing a connecton between a first one of said lines and a second one of said lines,'means included in said machine switching means for causing said individual signal of said second line to operate, means independent of said first line for causing said common signal to operate at the expiration of a predetermined period of time following the operation of said individual signal, and means whereby a third one of said lines may establish a conversational circuit with said first line.

11. In a telephone system, telephone lines, an individual signal for each of said lines,

common signal for said lines, means associated with each of said lines for causing said common signal to operate in a distinctive manner, machine switching means for interconnecting said lines, means included in said machine switching means responsive to the establishment of a connection between two of said lines for causing the individual signal. of the called one of said lines to operate, means independent ofthe calling one of said lines for thereafter causing the common signal to operate in a manner to identify the called one of said lines, means whereby a second connection may be established through said machine switching means between a third one of said lines and the pair of lines involved in the first mentioned connection, and means responsive to the establishment of the second connection for causing the operation of said common signal to cease.

1 In a telephone system, telephone lines, an individual signal for each of said lines, a common signal for said lines, means associated with each of said lines for causing said common signal to operate in a distinctive manner, machine switching means for interconnecting said lines, means included in said machine switching means responsive to the establishment of a connection between two of said lines for causing the individual signal of the called one of said lines to operate, means independent of the calling one of said lines for causing the common signal to operate at the expiration of a period of time following the operation of said individual signal, and means whereby a second connection may be established through said machine switching means between a. third pne of said lines and the two first mentioned mes. a

13; In a telephone system, telephone lines, a signal individual to each of said lines, a signal common to said lines, means individual to each of said lines for causing said common signal to'opera-te in a distinctive manner, means whereby the individual sig nals of said lines may be actuated, and means whereby said common signal may be selectively actuated to identify the line whose individual signal is being actuated after the latter signal has been in operation a definite period of time.

14. In a telephone system, telephone lines, a signal individual to each of said lines, a signal common to said lines, means individual to each of said lines for causing said common signal to operate in a distinctive manner, 9

means whereby the individual signals of said lines may be actuated, means whereby said common signal may be selectively actuated to identify the line whose individual signal is being actuated after the latter signal has been in operation a definite period of time, means whereby a different line may be connected to the line whose individual signal has been actuated, and means responsive to the last named connection for causing the operation of said common signal to cease.

In witness whereof, I hereunto subscribe my name this 17th day of July, A. D., 1919.

HENRY P. CLAUSEN. 

